Method and apparatus for separating the roving wound on packages from the flyers of a roving frame or the like, and for securing the roving end to the packages before doffing

Abstract: To secure the end of the roving (5) to packages (9) before their doffing from a roving frame, it is proposed to initially raise the package support carriage (2) into a position such that the lower end (4a) of the tubes (4) is at the level of the compressor (16) of the flyers (6), then rotate the packages (9) and flyers (6) through a few revolutions in order to wind and secure the roving (5) onto the lower end portion (4a) of the tubes (4), after which the carriage (2) is lowered to break the roving (5) in the section between the lower end (4a) of the tubes (4) and the flyers (6). Preferably, before lowering the packages (9), a reserve of roving (5) is created by slowly rotating the flyers (6) and packages (9) through a few revolutions, to simultaneously twist the roving (5) and strengthen it.

Description: This invention relates to a method and apparatus for separating the roving wound on packages from the flyers of a roving frame, and for securing the roving end to the packages before doffing. After winding the roving onto packages in a roving frame and before removing the packages from the frame, the roving is normally broken in the section between each package and the relative flyer following lowering of the package carriage, the roving end then being secured to the respective package by the operator to prevent it from unwinding during the subsequent package doffing and transportation. The halting of the roving for this purpose logically requires time, during which the frame has to remain at rest, this continuing until this operation has been carried out on all the packages, and hence for a relatively lengthy time. The operation itself is rather uncomfortable for the operator, who has to kneel to first locate the free end of the roving and then arrange it so that it does not unwind. The need to reduce the operating time on each package as much as possible for economic reasons carries the risk that the work is not always properly carried out and that the badly secured roving end of some packages may subsequently become released and lead to the unwinding of part of the roving, so prejudicing correct package feed to the next process. Devices are known which after the packages have been removed from the roving frame retain the roving end in contact with the winding to prevent its unwinding. These devices are however only provided along, and are only effective along, the package transport chain downstream of the roving frame and are therefore not able to prevent accidental unwinding of the roving between the frame and the commencement of the transport chain. In addition they do not eliminate the cost and unproductive time deriving from the human intervention in securing the roving to the packages on the frame. To prevent possible unwinding of the roving during that part of the package travel between the frame and the overhead conveyor, it has also been proposed to rotate the packages in the direction of winding of the roving against a stationary surface during their transport. Again, this does not totally eliminate the possibility of roving unwinding and in addition the means proposed to prevent this unwinding are rather complicated and unwieldy, so that the advantage of their use is relative. To solve the said problems, EP-A-0 467 475 has recently proposed a method and apparatus in which when the winding of the roving on the packages is complete, the packages at rest on the package support carriage are lowered until the upper end of the relative tubes reaches the height of the compressor of the respective flyers, after which the packages are rotated in order to wind a few turns of the roving under tension onto the upper end part of the tubes. The package support carriage is then further lowered to the doffing position, this producing breakage of the roving in that section between the upper end of the tubes and the relative flyers. To more reliably secure the roving turns onto the upper end of the relative tubes, an annular recess or a roughened portion is provided on the upper end of the tubes in order to increase friction and hence the stability of the turns against accidental unwinding. EP-A-467,475 represents the closest prior art with respect the present invention. This method and the relative apparatus have the substantial advantage of achieving completely automatic operation on all the frame spindles in fixing the roving end before doffing, with a considerable time and cost saving. EP-A-409 755 discloses a technique directed to make an appropriate roving end remaining on the roving frame, after the doffing of the completed package. According such reference the breaking of the roving is caused by tangential stress. The object of the present invention is to further improve said method and the relative apparatus such as to simplify the operations involved in locking the roving end on termination of package formation in a roving frame or the like, by ensuring effective retention of the roving end even without the use of grooves or roughened surfaces or the like on the tubes in the roving retention region and facilitating the gripping of the end for the subsequent processes. A further object is to provide a method and relative apparatus which can also be applied to normal roving frames already in use, without problems. These objects are attained by a method according to the features of claim 1. The method of the invention is implemented by an apparatus in a roving frame according to the features of claim 10. Advantageously, the apparatus can be also arranged to induce a slight rotation of the packages in the opposite direction to normal running, but with the flyers and roving feed at rest, so as to create a free length of roving before raising the carriage. Hence a method and apparatus according to the invention not only eliminates all manual action in securing the roving end to the respective packages, but results in completely automatic operation simultaneously on all spindles, with considerable time and cost saving. Advantageously, the binding of the roving end onto the lower end portion of the tubes, ie the portion between the end engaged by the package rotator and the lower frusto-conical package part, results in a retention action on the roving by the lower frusto-conical part of the package during the breaking when the package is lowered from the respective flyer, hence the stability of the binding is not prejudiced. In addition the roving binding in the lower region of the package tube is better accessible to the operator, who has to grip the end of the packages hanging on the creel of the spinning machine in order to thread it into the spinning machine, even though constructionally the creel is higher. In addition the tubes do not need to be provided with an annular recess or special surfaces for improving the grip on the roving. Further details and advantages of the invention will be more apparent from the description of some preferred but non-limiting embodiments thereof, illustrated by way of example on the accompanying drawings, in which: Figure 1 is a partly sectional, partly schematic side elevation of a roving frame provided with an apparatus according to the invention; Figures 2a, 2b, 2c, 2d and 2e are side elevations showing successive steps in the method of the invention; Figures 3a, 3b, 3c and 3d are side elevations showing certain steps in a modification of the method of Figures 2a-2e; Figure 4 is a perspective view of a flyer compressor particularly advantageous for implementing the method of the invention; Figure 5 is a section on the line V-V of Figure 4. Figure 1 shows a roving frame of known type, indicated overall by 1 and comprising a carriage 2 carrying a plurality of package rotators 3 in a known arrangement, for rotating respective tubes 4 on which the roving 5 provided by rotating flyers 6 is wound. The carriage 2 can be lowered and raised, there being associated with it vertically guided racks such as that indicated by 7, engaging respective pinions 8 rotated by a motor schematically indicated by M1. The arrangement can be such that when in its lowest position the carriage 2 inclines as indicated by dashed lines, to orientate the packages 9 in their inclined doffing position, in known manner. The package rotators 3 are rotated in known manner by a gear transmission such as that indicated by 10, driven by a motor M2. The mechanical connection between the transmission elements carried on the carriage 2 and those carried within the stationary part of the roving frame 1 is effected such as to maintain this connection in all positions of the carriage 2, using an arrangement which is known and therefore not illustrated in detail. The flyers 6 are rotated by a transmission 11 driven by a motor indicated schematically by M3. The roving 5 reaches the flyers 6 from a drafting unit 12 of known type, which receives the sliver 13 from feed cans 14. The active rollers of the drafting unit 12 are rotated by a motor M4. The motors M1, M2, M3 and M4 are connected to a control unit 15 arranged not only to operate these motors for the various winding operations but also to operate them in certain sequences and manners described hereinafter, in order to automatically achieve separation and locking of the roving 5 on the respective packages 9 on termination of winding, before doffing the packages and replacing them with empty tubes 4. When the roving 5 has been completely wound on the packages 9, these are in the position shown in Figure 2a, with the compressor 16 of the respective flyers 6 at the lower end of the cylindrical part 9a of the packages 9. When in this position the packages 9 are preferably made to undergo a small rotation (for example of 60° and with the flyers and feed halted) in the reverse direction to normal running, ie in the direction of the arrow R of Figure 2a, which is the opposite direction to winding and hence forming a free length of roving which enables the compressor 16 of the flyers 6 to be aligned with the lower end of the packages 9 without breakage of the roving 5 occurring. The packages 9 are then raised (arrow S) together with the carriage 2 by a command to the motor M1, until the lower end 4a of the relative tubes 4 is raised to the level of the compressor 16 of the respective flyers 6 (Figure 2b). In this position a length 5a of roving 5 is created extending from the last turn wound on the package 9 to the lower end 4a of the tube 4. By means of the motors M2 and M3 the packages 9 and flyers 6 are now rotated a few revolutions in the winding direction T, in order to wind a few turns of roving 5 under tension onto the lower end 4a of the respective tubes 4 and hence secure it thereto (Figure 2c). For this purpose the machine is controlled so as to wind the roving from the drafting unit under tension about the diameter of the tubes 4. To ensure particularly effective securing of the roving 5, the tubes 4 could be provided in this end part with an annular groove, preferably of rectangular cross-section for receiving said turns of roving 5 and effectively retaining them taut and compressed in the annular groove. Alternatively the lower end part 4a of the tubes 4 could be provided with a roughened or knurled or otherwise worked region for providing a more effective retaining or securing action on the wound roving 5. At this point the roving 5 is preferably reinforced by rotating the packages 9 and flyers 6 at equal speed in the normal running direction, in order to reinforce that portion of roving 5 between the flyers 6 and the drafting unit 12. This rotation is effected for a certain number of revolutions depending on the type of roving being worked. During this step the roving feed is halted. The packages 9 and flyers 6 are then advantageously rotated backwards for example through an angle of 270°, to hence slacken and remove a few degrees of twist from the roving 5 to facilitate its subsequent breakage within its free length. After this procedure the control unit 15 causes the package carriage 2 to descend (vertical arrow A) with simultaneous rotation of the packages 9 in the direction of the arrow R on Figure 2d through an angle for example of 270°, while maintaining the flyers 6 at rest, so as to form a reserve length 5b of roving and at a certain point cause the roving 5 to break by tearing, within the section between the lower end 4a of the tubes 4 and the respective flyers 6 (Figure 2d). The package carriage 2 is finally made to descend into a position such that the top of the tubes 4 is below the minimum level of the flyers 6 and there is no longer any possibility of interference between these and the tubes (Figure 2e). At this point the carriage 2 is in the doffing position and can be inclined for the doffing of the packages 9. Instead of inclining the carriage 2, it could also be possible to move the carriage 2 parallel to itself in a horizontal or substantially horizontal direction, while suitably guiding the carriage (arrows L). The packages 9, ready for doffing, now have the end of the roving 5 secured to the respective tubes 4 without any human intervention having been required for this. All the packages 9 of the roving frame have undergone the same action, with substantial time and cost savings. It should be noted that a free length of roving 5 remains, the length of which depends on the effective point of breakage of the roving 5. This free length does not however create any difficulties, and in fact facilitates location of the roving end when the package reaches the subsequent ring spinning machine. Because of the reliable retention of the roving end, no special precautions are required at any point along the path taken by the packages between the roving frame and the ring spinning machine, with consequent simplification of transport devices compared with those currently in use. It will be apparent that with the method and apparatus of the invention no significant structural modifications are required to the traditional roving frame, it being sufficient to provide a determined sequence of commands for the drive members of the frame on termination of normal package formation, in order to automatically achieve roving stoppage and breakage. The required sequence can be easily achieved using a suitable electronic card or in any event by known methods. As stated, before raising the packages 9 into the position shown in Figure 2b, it is preferable to create a suitable reserve 5a of roving 5 to prevent the roving undergoing premature breakage. As illustrated in Figures 3a-3d, it is also possible to slowly rotate the flyers 6 and packages 9 for a few revolutions in the direction indicated in Figure 3b with the feed halted, ie with the drafting unit at rest (motor M4 halted) and the packages 9 in the raised position of Figure 3a (corresponding to that of Figure 2a), so as to additionally twist the roving 5 (Figures 3b and 3c) and hence strengthen it, before reaching the position of Figure 3d, which corresponds to the position of Figure 2b. Advantageously the compressor 16 of the flyers 6 can have a configuration as shown in Figures-4 and 5. It is provided with a hole 16a for passage of the roving 5, which towards the package 9 is guided in a recess 16b formed in the plate of the compressor 16 at the hole 16a and having a depth which progressively decreases in the direction of movement of the roving 5. The plate of the compressor 16 is bent outwards along the (horizontal) longitudinal edges 16c of the compressor 16, to thus create two inclined surfaces 16d converging towards the packages 9 at the opposing edges of the substantially plate-like central part of the compressor 16. These inclined surfaces 16d facilitate the relative movement between the packages and flyers in the axial direction of the packages 9 at the package conic portions. Specifically, during the descent of the packages 9 in passing from the position of Figure 2c to the position of Figure 2d, the aforedescribed configuration facilitates the radial withdrawal of the compressor 16 from the lower end 4a of the tubes in contact with the lower conic portion of the packages 9, without hindering the relative movement and without damaging the wound roving. The wound part of the packages can hence be correctly unwound in the downstream spinning machine without irregularity. Various modifications can be made in addition to those described without leaving the scope of the present invention. The roving frame could obviously be of automatic doffing type without this implying any modification in the method and apparatus of the invention.

Claims: A method of breaking roving (5) wound on tubes (4) to form packages (9) from flyers (6) of a roving frame and for securing the effective retention of the roving end to the packages (9) before doffing the packages from the roving frame comprising the steps of: a) winding roving (5) upon the tubes (4) to form packages (9), b) terminating the winding of the rovings, c) moving the packages (9) until an end of the tubes (4) is substantially adjacent the compressors (16) of the flyers (6) , d) thereafter rotating the tubes (4) and flyers (6) to wind a few turns of the rovings under tension upon the tube ends, and e) thereafter moving the packages (9) to break the rovings between the tubes (4) and the compressors (16), characterised in that the packages (9) are raised until a lower end (4a) of the tubes (4) is adjacent the compressors (16) before winding the turns upon the tube ends (4a), and the packages (9) are lowered vertically to break the rovings (5). The method as claimed in claim 1, wherein the winding of step a) is carried out by rotating the packages (9) in a first direction, characterised in that, prior to raising the packages (9) pursuant to step c), the packages (9) are rotated slightly in a second direction opposite the first direction with the flyers (6) and the roving feed at rest to create a free length of roving and thereafter the step d) is carried out. The method as claimed in claim 1, characterised in that, after performing the step d), the packages (9) and flyers (6) are rotated at the same speed in a normal running direction, while the roving feed is halted, to provide the rovings with additional twist and reinforcement. The method as claimed in claim 3, characterised in that, prior to performing step e), the packages (9) and flyers (6) are rotated backwards opposite to the package winding direction to slacken the rovings (5) and remove a few turns of twist from the roving. The method as claimed in claim 1, characterised in that, during the performance of the step e), the packages (9) are rotated in a direction opposite to the winding direction of step a) while the flyers (6) are maintained at rest, to form a reserve length of roving (5) between the tube lower ends (4a) and the compressors (16) before the performance of the step e). The method as claimed in claim 1, characterised in that the tube (4) has an annular groove at the tube lower end (4a), and the step d) is performed by winding the few roving turns taut in the annular groove. The method as claimed in claim 1, characterised in that the tube (4) has a roughened surface at the tube lower end (4a), and the step d) is performed by winding the few roving turns on the roughened surface. The method as claimed in claim 1, characterised in that the breaking of the roving is carried out during the lowering of the package (9) in vertical direction. A method of breaking roving (5) wound on tubes (4) to form packages (9) from flyers (6) of a roving frame and for securing the effective retention of the roving end to the packages (9) before doffing the packages from the roving frame comprising the steps of: a) winding rovings (5) upon tubes (4) to form packages (9) on the tubes (4), by rotating the packages (9) and the flyers (6) in a first direction, b) moving the packages (9) until the ends of the tubes (4) reach the height of the compressors of the flyers (6), c) again rotating the packages (9) and flyers (6) to wind a few turns of fed roving under tension upon the end of the tubes (4), d) further moving the packages (9) relative to the flyers (6) to break the roving in a roving section between the tube (4) and the flyer (6), characterised in that it further comprise the steps of: a1) at the conclusion of the step a), rotating the package (9) in a second direction opposite to the first direction through a predetermined angle with the flyer (6) and the roving feed halted, b1) the step b) is carried out by raising the package (9) until the lower ends (4a) of the tubes (4) reach the height of the compressors (16) of the flyers (6), e) at the conclusion of step d), rotating the package (9) and flyers (6) at equal speed in the first direction for a few revolutions with roving feed halted to provide the rovings (5) with additional twist and reinforcement, f) thereafter rotating the flyers (6) and packages (9) in the second direction through a predetermined angle to slacken the twist in the rovings (5), g) lowering the packages (9), h) rotating the lowered packages (9) in the second direction to further slacken the twist in the roving (5), i) further lowering the packages (9) relative to the flyer (6) to break the rovings in a roving section between the tube lower end (4a) and the flyers (6). An apparatus for breaking roving (5) wound on tubes (4) as packages (9) from flyers (6) of a roving frame and for securing the effective retention of the roving end to the packages (9) before doffing the packages from the roving frame, comprising a carriage (2) for supporting the tubes (4) relative to the flyers (6) and compressors (16), means (M1,7,8) for raising and lowering the carriage (2), means (M2) for rotating package rotators (3) supporting the tubes (4), means (M3) for rotating the flyers (6), such means being operated for moving the packages (9) until an end of the tubes (4) reaches the height of the compressors (16) of the flyers (6), for again rotating packages (9) and flyers (6) to wind a few turns of fed roving under tension upon the end of the tubes (4) and further for moving the packages (9) relative to the flyers (6) to break the rovings in a roving section between the ends and the flyers characterised by comprising means (15) for controlling the operation a) of the raising and lowering means (M1,7,8) to raise the carriage (2) to a position at which the lower end (4a) of the tubes (4) reach the height of the compressor (16) of the flyers (6), b) of the package rotating means (M2) and the flyer rotating means (M3) to rotate for a few revolutions to wind a few turns of the rovings (5) under tension about the tube lower ends (4a), and c) of the raising and lowering means (M1,7,8) to lower the carriage (2) and the packages (9) to its doffing position thereby causing the rovings (5) to break at a point between the packages (9) and the tube lower ends (4a) giving the effective retention of the roving ends to the packages (9) for their subsequent spinning. The apparatus as claimed in claim 10, characterised in that the control means (15) controls the operation of said package rotating means (M2) to operate said package rotating means (M2) to rotate the package (9) during the lowering of the carriage (2). The apparatus as claimed in claim 10, characterised in that the control means (15) is operative to selectively operate said package rotating means (M2) to rotate the packages (9) a small rotation in a direction opposite to the winding direction with the flyers (6) and the associated roving feed means (12) halted to thereby create a free length (5b) of roving before the raising of the carriage (2). The apparatus as claimed in claim 10, characterised in that the control means (15) is operative to selectively operate said package rotating means (M2) and said flyer rotating means (M3) to rotate the package (9) and the flyer (6) at equal speed in the normal winding direction while an associated roving feed means (12) is halted to impart additional twist and reinforcement to the rovings (5) before the lowering of the carriage (2) . The apparatus as claimed in claim 10, characterised in that the control means (15) is operative to selectively operate said package rotating means (M2) and said flyers rotating means (M3) to rotate the packages (9) and the flyers (6) in a direction opposite to the winding direction to slacken the twist in the rovings (5) before the lowering of the carriage (2). The apparatus as claimed in claim 10, characterised in that the control means (15) is operative to continue the lowering of the carriage (2) after the breakage of rovings (5). The apparatus as claimed in claim 10, characterised in that each flyer (6) comprises a compressor (16) bent outwards along its longitudinal edges to form two converging inclined surfaces (16d) converging towards the packages (9) at the opposite edges of a substantially plate -like central portion of the compressor (16).

Inventors: BORGOGNI ANGELO, LOCATELLI CLAUDIO, BORGOGNI, ANGELO, LOCATELLI, CLAUDIO
Applicants: MARZOLI SPA, MARZOLI S.P.A.
Application year: 1994
Main classification: D01H9
IPC codes: D01H9, D01H1